Jets of high pressure fluids, such as saline, have been used in various surgical and medical applications to, for example, remove tissue, debride wounds, and drive small burrs and cutters. Such uses are described in U.S. Pat. Nos. 5,713,878, 5,871,462, 5,944,686, and 6,216,573, owned by the assignee of the present application, as well as in patents to others.
Devices using these water jets typically have two principal subsystems. One part compresses the fluid to high pressure, at least about 500 to 1,000 pounds-per-square inch (psi), and more typically from about 1,000 to 25,000 psi or more, with a preferred range, dependent on the end use of the device, that will often be narrower, such as 6,000 to 15,000 psi, 3,000 to 12,000 psi, or 10,000 to 20,000 psi. (1000 psi is about 7 MPa.) The pressurized fluid is conveyed through flexible tubing to a handpiece, which may utilize the pressurized fluid in various ways. For example, the handpiece may permit the surgeon to direct a stream of fluid at tissue, such as in a tissue removal or debriding operation, or it may use the stream of fluid to drive a rotating burr or cutter. Typically, the handpiece and tubing are sterile, while the pump is internally sterile but located outside of the sterile field. In some applications, the handpiece may be disposable, as cleaning after an operation is not necessarily reliable.
Many prior art methods for connecting high-pressure liquid streams involve tightening screw connections, typically in order to compress and deform gaskets. Gaskets in a high-pressure system can be problematic, because, to the extent that they are elastomeric, they tend to deform and extrude, while stiffer ones may not seal well.
Medical procedures often require the use of more than one type of handpiece. It is therefore useful to be able to detach the handpiece from the high-pressure supply and change the handpiece during a procedure. This procedure requires simplicity of operation in a sterile field, and preferably does not involve manipulations difficult to conduct with gloved hands. At the same time, the connection must be able to sustain high pressures as described above without leaking. Any such mechanism preferably is inexpensive, so as to be disposable, and it should be sterilizable.